JPH08273161A - Disk-shaped recording medium - Google Patents

Abstract

PURPOSE: To improve the memory capacity over the entire part by recording reference patterns to be used as a reference at the time of reproducing of recording data in recording and reproducing regions. CONSTITUTION: The exact specification of writing positions in a ROM region is made possible by press accuracy in the case only the tops of the respective zones of the RAM regions are provided with the reference regions where 2T patterns and 8t patterns are recorded and, therefore, the 2T patterns and 8T patterns may be omitted as shown in Fig. (b). The useless recording regions are thus omitted as compared with the case the tops of the respective sectors are provided with the reference regions in the RAM region as well. The storage capacity of the optical disk is correspondingly improved. Only the top of the RAM region may be provided with the reference region as shown in Fig. (c) and in such a case, the useless recording regions of the RAM region are omitted and further, the storage capacity of the optical disk is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk-shaped recording medium such as a magneto-optical disk, a compact disk, a magnetic disk or the like, and particularly to a novel format capable of improving the recording capacity.

[0002]

2. Description of the Related Art Conventionally, recording / recording of various data is performed by scanning a track formed in a concentric circle shape or a spiral shape with a laser beam.
In an optical disc system for reproduction, a CLV system in which an optical disc is rotationally driven at a constant linear velocity (CLV) to record / reproduce data, or an optical disc has a constant angular velocity (CA).
CAV for rotating / driving V) to record / reproduce data
The type is known. In addition, there is a continuous servo system that performs tracking control using pregrooves that are continuously provided along the track, and a sample servo system that performs tracking control that uses servo areas discretely provided on the track. Are known.

Further, as the optical disc, a recordable RAM disc such as a read-only ROM disc, a write-once disc, a magneto-optical (MO) disc, a ROM area and RA.
A hybrid disc having an M area and the like are known, and a partial ROM disc having an extremely high recording density corresponding to multimedia is being put to practical use.

[0004]

However, although there has been a demand for a large capacity optical disk in the past, for example, in the case of the above hybrid disk, a ROM area and RA are used.
Since the same format is adopted in the M area and unnecessary information is recorded in the ROM area, the storage capacity cannot be improved. Therefore, in order to maintain the predetermined storage capacity, it is impossible to make the size smaller than ever, and in order to achieve the storage capacity more than ever, the disk itself has to be made large. There is a problem that leads to an increase in size of the disc player device or the like.

The present invention has been made in view of the above problems, and can improve the storage capacity, thereby contributing to downsizing of a disc player device or the like. For the purpose of providing.

[0006]

A disk-shaped recording medium according to the present invention is a disk-shaped recording medium having a read-only area and a recording / reproducing area, and is recorded only in the recording / reproducing area when reproducing recorded data. It has a reference pattern as a reference.

The disk-shaped recording medium according to the present invention is a disk-shaped recording medium having a read-only area and a read-write area, wherein the recording / playback area has a narrower track pitch than the read-only area.

Further, the disk-shaped recording medium according to the present invention is a disk-shaped recording medium having a read-only area and a read-write area, wherein the read-only area has a higher linear density than the record-play area.

Further, in the disc-shaped recording medium according to the present invention, in the disc-shaped recording medium having the reproduction-only area and the recording / reproducing area, only the recording / reproducing area has alternation information indicating a defective position.

Further, the disk-shaped recording medium according to the present invention has a sample-servo disk-shaped recording having a read-only area and a recording / reproducing area, and servo areas in which servo patterns are recorded at predetermined intervals in each area. In the medium, a level-down information recording area, which is provided before each servo area of the recording / reproducing area, in which level-down information for recording a laser level of a recording level as a reproduction level is recorded, and each servo of the recording / reproducing area It has a level-up information recording area which is provided in the latter part of the area and in which level-up information for re-recording the laser level set as the recording level by the level-down information is recorded.

The disc-shaped recording medium according to the present invention has at least a reproduction-only area, and the head of the reproduction-only area or the head of each area obtained by dividing the reproduction-only area into a plurality of areas, It has a reference pattern used as a reference when reproducing the recorded data.

Further, the disk-shaped recording medium according to the present invention has at least a read-only area, and in this read-only area, the track pitch is equal to or larger than the diameter of the pinhole generated on the medium, and each track is rotated. Error correction of the recorded data, which is recorded collectively at the end of the reproduction-only area or the end of each area obtained by dividing the reproduction-only area into a plurality of areas. It has error correction information for performing.

[0013]

First, in the reproduction-only area, the writing position can be accurately specified by the pressing precision, so that it is possible to omit the recording of the reference pattern which is the reference when reproducing the recording data. Therefore, in the disc-shaped recording medium according to the present invention, the reference pattern is recorded only in the recording / reproducing area of the reproduction-only area and the recording / reproducing area. As a result, the reference pattern to be recorded in the read-only area can be omitted, and the storage capacity of the disc-shaped recording medium can be improved.

Next, in the read-only area, since the data level obtained during reproduction is higher than the data level obtained from the recording / playback area, the track pitch of the read-only area is made narrower than the track pitch of the recording / playback area. Also, the recorded data can be reproduced without any problem. Therefore, the disc-shaped recording medium according to the present invention records the record data by making the track pitch of the read-only area narrower than the track pitch of the read-write area of the read-only area and the read-write area. As a result, the storage capacity of the read-only area can be improved by the amount of narrowing the track pitch,
The storage capacity of the entire disc-shaped recording medium can be improved.

Next, in the reproduction-only area, the data level obtained during reproduction is higher than the data level obtained from the recording / reproduction area. Therefore, even if the linear density of the reproduction-only area is increased, the recorded data can be reproduced accurately. It can be carried out. Therefore, the disk-shaped recording medium according to the present invention records the record data by making the linear density of the read-only area of the read-only area and the read-write area higher than that of the read-write area. As a result, the storage capacity of the read-only area can be improved, and the storage capacity of the entire disc-shaped recording medium can be improved.

Next, if there is a defect such as a scratch on the disk-shaped recording medium, it is not possible to record the record data at the defective position. Therefore, it is necessary to record the replacement information indicating the defective position in advance, and record the recording data while reproducing the replacement information and avoiding the defective position. However, this alternation information is almost unnecessary in the read-only area formed by pressing. Therefore, the disc-shaped recording medium according to the present invention records the alternation information only in the recording / reproducing area of the reproduction-only area and the recording / reproducing area. As a result, the replacement information that should be recorded in the read-only area can be omitted, so that the storage capacity of the entire disc-shaped recording medium can be improved.

Next, in a so-called sample servo type disk-shaped recording medium in which predetermined servo patterns are recorded at predetermined intervals, the laser level, which is the recording level at the time of recording, is lowered to the reproduction level immediately before the servo pattern. It is necessary to reproduce the servo pattern, return the laser level to the recording level immediately after reproducing the servo pattern, and continue recording. Therefore, recording of level-down information, which is information for dropping the laser level to the reproduction level immediately before the servo pattern, and recording of level-up information, which is information for returning the laser level to the recording level immediately after the servo pattern. Records are required. However, the level-down information and the level-up information are control information necessary only at the time of recording and are not necessary in the reproduction-only area. Therefore, the disk-shaped recording medium according to the present invention, which is the disk-shaped recording medium of the sample servo system,
Among the reproduction-only area and the recording / reproducing area, only the recording / reproducing area is provided with a level-down information recording area in which the level-down information is recorded and a level-up information recording area in which the level-up information is recorded. This makes it possible to omit the level-down information and level-up information that should be recorded in the reproduction-only area. Therefore, since the level-down information and the level-up information can be omitted, the storage capacity of the read-only area can be improved, and thus the storage capacity of the entire disc-shaped recording medium can be improved.

Next, in the reproduction-only area, since the writing position can be accurately specified by the press accuracy, it is possible to omit the recording of the reference pattern used as the reference when reproducing the record data. By doing so, it is possible to reproduce the recorded data more accurately. However, if a reference pattern is recorded at the beginning of all the sectors, the storage capacity will be reduced. Therefore, the disc-shaped recording medium according to the present invention records the reference pattern at the beginning of the reproduction-only area or at the beginning of each area obtained by dividing the reproduction-only area into a plurality of areas. As a result, the number of reference patterns to be recorded in the reproduction-only area can be reduced to one or several. Therefore, the storage capacity of the disk-shaped recording medium can be improved by the amount that this reference pattern can be reduced. The disc-shaped recording medium in this case may have only the reproduction-only area or may have the recording-reproduction area together with the reproduction-only area.

Next, when forming a disk-shaped recording medium, holes called pinholes of, for example, about 80 μm to 100 μm may occur. In the case of the recording / reproducing area, even if this pinhole occurs, that portion may be stored as a defect position, and the recording data may be recorded / reproduced so as to avoid it. The recording data cannot be recorded avoiding the above-mentioned pinhole because the recording data is recorded by the above, and when the pinhole is generated, the disc-shaped recording medium itself is It becomes a defective product. Here, when the recording data is recorded on the disk-shaped recording medium, the error correction information is recorded, and the correction capability by the error correction information is one sector. For this reason, if the pinhole is generated between two tracks, error correction becomes impossible. Also, even if the above error correction information is added,
If this is added to each sector, the storage capacity will be reduced by the error correction information. Therefore, in the disk-shaped recording medium according to the present invention, a data sector is formed in the read-only area so as to have a track pitch equal to or larger than the diameter of a pinhole generated on the medium and to be completed every track.
Then, error correction information for performing error correction on the recorded data is collectively recorded at the end of the read-only area or at the end of each area obtained by dividing the read-only area into a plurality of areas. As a result, the pinhole generated at the time of forming the medium does not clog into two tracks, and it is possible to perform the error correction by the error correction information. Moreover, since the error correction information is collectively recorded, the number of error correction information to be added can be reduced and the storage capacity can be improved. The disc-shaped recording medium in this case may have only the reproduction-only area or may have the recording-reproduction area together with the reproduction-only area.

[0020]

Embodiments of the disk-shaped recording medium according to the present invention will be described below in detail with reference to the drawings.

The disc-shaped recording medium according to the present invention can be applied to an optical disc as shown in FIG. This first
In the optical disc according to the embodiment, one track has one track, for example.
It is divided into 400 segments. This segment consists of address segment ASEG and data segment DS
EG is present.

The address segment ASEG has 14
One segment is provided for each segment, and 100 segments are provided for one track. In the address segment ASEG, position information in the radial direction and position information in the tangential direction are recorded as prepits. Also, the address segment ASE
One frame extends from G to the next address segment ASEG, and 100 frames are formed in one round of the track. The address segment ASEG and the next address segment ASEG
13 segments between and are the data segment DSE
It is G. This data segment DSEG is 1
There are 1,300 segments on the circumference.

Next, one segment is constituted by a total of 216 servo locks, that is, servo areas ARs for 24 servo clocks and data areas ARd for 192 servo clocks. In the address segment ASEG, the data area ARd is composed of an address area ARda and a laser control area ARdwapc. Further, in the servo area ARs, for example, as shown in FIG. 2, three pits PA, PB, and PC each having a length of 2 servo clocks are pre-recorded at a distance of 5 servo clocks or more, and 6 Focus sample areas ARfs for clocks are provided.

As described above, by making the pits PA, PB, and PC of the servo area ARs each two servo clocks long, the mirror portion can be reduced, and ghost pits and the like generated during disk formation are generated. Can be difficult. Therefore, the difficulty of forming pits can be reduced, and the servo signal can be stably reproduced. Also, each pit PA, PB, PC
By separating 5 servo clocks or more, the interference between pits can be made extremely small.

Next, the second pit PB located in the 11-12 clock period and the third pit PC located in the 16-17 clock period are ± 1/4 from the center of the track.
The wobble pits are provided by displacing only the tracks, and tracking error information can be obtained by detecting the difference between the amplitude values of the reproduction outputs of these pits PB and PC. Also, these pits PB,
The clock phase information can be obtained by detecting the difference between the amplitude values of both edges of the reproduction output of the PC, and the addition of this phase information can obtain the clock phase information independent of tracking. It is designed to be used.

Next, whether the segment of the first pit PA at the beginning of the servo area ARs is the address segment ASEG or the data segment DSE.
In addition to indicating whether it is G, it also indicates whether it is the beginning of a sector or the next segment is the beginning of a sector.

Specifically, the first pit PA is 9 to 1
When it is located in the 0 clock period, it indicates that the segment is the data segment DSEG, and when it is located in the 2 to 3 clock period, it indicates that the segment is the address segment ASEG, and it is in the 3 to 4 clock period. If located, it indicates that the segment is the data segment DSEG that is the beginning of the sector.
When it is located within the period of up to 5 clocks, it indicates that the next segment is the data segment DSEG which is the head of the sector.

The information indicated by the first pit PA can be identified by detecting the position having the maximum amplitude value by the so-called differential detection method, which is the maximum difference value detection as shown in FIG. 3, for example. can do.

As described above, the first pit PA at the beginning of the servo area ARs provides information indicating whether the segment is the address segment ASEG or the data segment DSEG and the information indicating whether the sector is the beginning or the next segment is the beginning of the sector. By providing the data, it is not necessary to provide the sector number and the track address for each sector, and the redundancy of the data area can be lowered.

In the address segment ASEG,
As shown in FIG. 4, 16-bit track addresses [AM] and [A] are used as information on the radial position of the disc.
2], [A3], and [AL] and their parity [P], and the frame codes indicating frame addresses [FM] and [FL] as tangential direction information are gray-coded in advance, respectively. It is recorded in the pit.

In the above access code, a 16-bit track address is divided into 4 bits, and when the least significant bit of the 4 bits is "1", the following 4 bits are AM = 15 to 12 bits (MSN). ) To A2 = 11
~ 8 bits (2SN), A3 = 7 to 4 bits (3S
N) and AL = 3 to 0 bits (LSN) in that order, the table conversion is performed on the value obtained by complementing 1 based on the gray code table as shown in FIG. Gray coded so that only one pattern changes. As the parity code, each bit of the access code [15, 11, 7,
3], [14, 10, 6, 2], [13, 9, 5, 5]
1], [12,8,4,0] and the number of "1" s is even, the result of taking a parity of 1 is recorded. As a result, the access code is formed on the disc in a data pattern as shown in FIG. 5, for example.

Next, the frame code divides the 8-bit frame address representing the tangential direction number of the address segment ASEG into 4 bits,
The upper 4 bits FM = 7 to 4 bits (MSN) and the lower 4 bits LM = 3 to 0 bits (MSN) are gray-coded and recorded by the same method as the above access code.
Although information of 8 bits can be recorded as this frame code, it is actually 0 to 99 which is the number of address segments ASEG.

Focus, read power APC,
It is difficult to accurately control the phases of various sample pulses when performing processing such as clamping of an RF signal, and fluctuations of ± 0.5 clocks or less occur. Therefore, the focus sample area ARfs of the servo area ARs is a mirror portion for 6 clocks so as not to receive pit modulation. As a result, a sampling space can be secured for each of the above processes, so that each of the signals can be reliably sampled without being affected by the pit modulation even if the clock changes.

Next, the data area ARd of the data segment DSEG is a data area A for 176 to 376 data clocks for recording normal data as shown in FIG.
Rda and pre-write area A for 12 data clocks
Rpr and post-write area A for 4 data clocks
It is formed with Rps. Above pre-write area AR
The pr is provided to secure a necessary distance from laser irradiation to a stable temperature of the disk and to be used as a clamp area for suppressing DC fluctuation due to birefringence of MO signal. Above post light area A
Rps is provided in order to eliminate the unerased portion by overwriting and to secure a distance that avoids interference from the groove edge.

This optical disc is bulk erased in one direction at the time of shipment. This allows it to be used without the need for a formatting operation. The pre-write area ARpr and the post-write area ARps are also included.
In, data having the same polarity as that of the bulk erase is recorded. As a result, data recording is performed before the temperature of the disk is stable, and stable reproduction output can be obtained even if data recording is not normally performed.

Here, the optical disk is magneto-optical (MO).
In the case of a recordable optical disk such as a disk, the groove Gr is provided in the data area ARd. As a result, it is possible to reduce the number of mirror portions and prevent the disadvantage that servo pits are adversely affected during disk molding. Since the groove Gr is not used for tracking, accuracy such as depth thereof is not required.

The above optical disk is a read-only ROM
In the case of a disc, as shown in FIG.
Anchor pit Pan for 3 clocks at the beginning of Rd
Is provided. As a result, it is possible to reduce the number of mirror portions and prevent the disadvantage that the servo pits are adversely affected during disk molding.

One data sector includes 66 bytes of reference area and 2048 bytes of user data (D0 to D0).
D2047), ECC 256 bytes (E1,1 to E1
6, 16), CRC8 bytes (CRC1 to CRC8),
It is composed of a total of 2418 bytes including a vendor unique 8 bytes (VU) and a user defined 32 bytes (UD).

As shown in FIG. 8, the reference area is composed of 4 blocks of 8T patterns and 2T patterns, and 2 bytes of all 0 patterns as a margin for setting the detected information. A specific pattern of 66 bytes is recorded. The above 1 block consists of 4 bytes of 8T pattern and 12 bytes of 2T
The 8T pattern is used to set a ternary level (high H, medium M, low L) in data detection, and the 2T pattern is a DC pit position due to recording power fluctuation or the like. It is used to correct the deviation during playback.

Then, in the data area ARd of the data segment DSEG, data other than the 66-byte reference area is scrambled, and further,
NRZI data is recorded for each segment.

Further, as shown in FIG. 9A, this optical disk has a GCP band for 736 tracks from the outer peripheral side,
2 track buffer tracks, 5 track control tracks, 2 track buffer tracks,
It has test tracks for 5 tracks. Further, R is an area in which the user can record and reproduce desired record data.
It has an AM area, a ROM area which is a read-only area, five test tracks, two track buffer tracks, five track control tracks, two track buffer tracks, and 820 GCP bands. .

This optical disc is a so-called zone CAV disc as shown in FIG.
The M area and the ROM area are respectively divided into 16 recording / reproducing zones and reproducing zones.

Here, the number of tracks in the zone is TRAC.
zone, and the number of data segments required for one sector in a certain zone is DSEGsec-zone,
The number of data segments per track is DSEGtr
As the ack, when the sectors are completed for each zone and the number of sectors is fixed, the number of sectors in the zone SCT
zone is SCTzone = TRACzone / DSEGtrac
k / DSEGsect-zone, and the number of tracks may be determined so that TRACzone = K · DSEGsect-zone. And K
The number of sectors SCTzone, which is determined by using a value close to the capacity per zone divided by the number of zones with respect to the total capacity, is assigned from the outer circumference, and the recording density of the innermost circumference part of the zone is set to a predetermined value. All parameters can be obtained by determining the clock (M) so that the density does not drop below the density.

In this case, as shown in FIG. 11, when a sector starts from a certain segment, the number of segments forming one sector and that sector are terminated, and even if there is an extra byte in the last segment, the next sector is Start with the next segment. As a result, at the beginning of the zone, it is possible to continuously form the section that always starts from the sector of the 0 frame code.

Although there is a possibility that the number of sectors in the innermost zone is not the same as the number of sectors in the other zones due to the relationship with the recording area, there may be a fractional number. By setting the zone, the capacity of the parity sector can be easily calculated.

In this optical disc, the user zone is divided into 16 zones as described above,
The number of data bytes included in one segment (byte / seg) and the number of segments per sector (seg / sector) are determined by the data clock DCLK multiplied by M / N of the servo clock SCLK.

That is, assuming that the number of servo clocks in the servo area ARs is N and the data clock is M / N times the servo clock, the number of servo clocks SCLKseg and the number of data clocks DCLKseg in one segment are set.
Becomes SCLKseg = 9N DCLKseg = SCLKsegM / N (N and M are integers).

Further, as described above, one track has 140
It is divided into 0 segments, 1300 of which are data segments DSEG, but since data is not recorded in the GCP band, 100 segments of 1300 data segments DSEG are recorded with GCP information such as media information. GCP segment GCP
Used as a seg, the GCP segment GCPseg is
As shown in FIG. 12, it is assigned to the data segment at the intermediate position of each address segment ASEG.

Then, the GCP segment GCPseg
Indicates the servo areas ARs and GCP as shown in FIG.
The GCP area ARgcp is composed of an area ARgcp and a blank ARblk. In the GCP area ARgcp, seven 4-bit data which are gray coded in the same manner as the access code, that is, [GCPH], [GCPH], [[GCPH], GCP2], [GCP3], [GC
PL] and its parity [P], and the page numbers [PNH] and [PNL] are gray coded and recorded in pits.

An error can be detected in the GCP code by adding a parity [P]. Also,
By adding page numbers [PNH] and [PNL], a plurality of media information and the like can be given as GCP information. Page number [PN
H] and [PNL] are [P
By recording the same information in [NH] and [PNL],
You can be robust against errors.

In the GCP area ARgcp,
As shown in FIG. 14, by arranging each GCP segment GCPseg in a state where the page number of the GCP segment GCPseg of the last 1 digit of the address (frame number) recorded in the address segment ASEG is matched, Misreading of the frame number of the address segment ASEG and the page number of the GCP segment GCPseg can be eliminated. Further, by repeatedly recording 10 pages, that is, 10 kinds of GCP information 10 times, it is possible to reduce misreading of each 10 kinds of GCP information.

Here, the above GCP segment GCPse
The GCP information recorded in g is, for example, as shown in FIG. 15, page number 0 is information indicating media information / media type, and bits 15 to 12 indicate the physical properties of the media such as the presence or absence of a group and the presence or absence of a sector mark. Information indicating the format is given, bits 15 to 12 give information indicating the format format of the medium, and bits 7 to 0 give information indicating the format of the medium such as MO and ROM.

The GCP information of page number 1 is shown in FIG.
As shown in FIG. 6, it is information indicating a data information / error correction format. Bits 15 to 8 give data information such as a sample servo system, logical CAV, NRZI coding, and bits 7 to 0 indicate an error correction format. Give information. As shown in FIG. 17, the GCP information of page number 2 is information indicating the outer peripheral SFP track physical address, and bits 15 to 0 give information indicating the outer peripheral side control track physical address. Also, the GCP information of page number 3 is, as shown in FIG.
Bit 15 is information indicating the track physical address.
Information of 0 to 0 gives the physical address of the control track on the inner circumference side. As shown in FIG. 19, the GCP information of page number 4 is information indicating the maximum read power, and bits 15 to 8 give information indicating the maximum read power. Bits 8 to 0 are preliminary information. The GCP information of page number 5 is information indicating the outer peripheral control track clock ratio / the number of segments per sector, as shown in FIG.
8 to 8 give information indicating the number of clock control of the outer circumference control track, and bits 8 to 0 give information indicating the number of segments per sector. Also, GCP on page number 6
As shown in FIG. 21, the information is information indicating the inner control track clock ratio / the number of segments per sector, and bits 15 to 8 give information indicating the number of clock control of the inner control track. ~ 0 gives information indicating the number of segments per sector. Also,
As shown in FIG. 22, the GCP information of page number 7 is information indicating the number of locks per segment / the number of servo clocks per segment, and bits 15 to 8 give information indicating the number of locks per segment. Bit 8 ~
A value of 0 gives information indicating the number of servo clocks per segment. As shown in FIG. 23, the GCP information of page number 8 is information indicating the number of segments per track, and bits 15 to 0 give information indicating the number of segments per track. Furthermore, GC of page number 9
The P information is information indicating the number of attress segments per track / spare as shown in FIG.
Information indicating the number of attress segments per track is given by 5 to 8, and bits 8 to 0 are preliminary information.

Next, in the control track, the above-mentioned 20 bytes of GCP information, 10-byte media information such as laser wavelength, reflectance, and track pitch, the number of bytes of various physical block addresses and data fields, and various areas. 70 bytes of system information such as the number of data clocks and the number of zones, plus definition data for each zone 3
Band information of 20 bytes is recorded.

In this control track, information A (A = segment number / track) indicating the number of segments (1 byte) per track, information B indicating the start track number (2 bytes) of each zone, and total track of each zone By recording the information indicating the number (2 bytes) and the information D (D = number of segments / sector) indicating the number of segments per sector (1 byte), for example, from the serial sector address, the physical The track address and physical segment address can be calculated.

That is, the serial sector address is converted into the zone number E and the offset number F using the table, and from the offset number F, F × D / A = G (quotient). ． ． By performing the calculation of H (remainder), it is possible to calculate the physical track address and the physical segment address in the zone by setting Physical track address = B + G Physical segment address = H 2.

In the optical disc having such a structure, the GCP zone extending over a plurality of tracks provides the media information as a gray code in the same format as the address information recorded in the address segment ASEG. The media information can be provided without the need for a decoder. Also,
No special signal generator is required for cutting. Further, the address information can be read while the reproducing device is reading the GCP, so that the position of the pickup can be reliably managed. Further, in the GCP zone, since the media information having the same content is provided a plurality of times around the track, it is possible to provide highly reliable media information to the reproducing device. Further, in the GCP zone, since each data segment DSEG located in the radial direction of each track gives the same media information, the media information can be read without tracking on the reproducing apparatus side. Furthermore, since the GCP zones are provided on the inner and outer circumference sides, it is possible to select either the inner or outer circumference start on the reproducing device side.

Next, in such an optical disc,
The reference area in which the 2T pattern and the 8T pattern are recorded is provided only at the head of each zone of the RAM area as shown in FIG. ROM above
Since the writing position of the area can be accurately specified by the pressing accuracy, as shown in FIG.
Recording of the T pattern and the 8T pattern can be omitted. Therefore, the reference area that should be provided in the ROM area can be omitted, and also in the RAM area, useless recording area can be omitted as compared with the case where the reference area is provided at the head of each sector. Therefore, the storage capacity of the optical disk can be improved accordingly.

In this case, the reference area may be provided only at the head of the RAM area as shown in FIG. As a result, it is possible to omit a useless recording area in the RAM area and further improve the storage capacity of the optical disc.

Next, when recording the recording data, in order to reproduce the predetermined servo pattern as described with reference to FIG. 2, the laser level which is the recording level is lowered to the reproduction level immediately before the servo pattern. It is necessary to perform an operation of reproducing the servo pattern by using the servo pattern, returning the laser level to the recording level immediately after the reproduction of the servo pattern, and continuing recording. Therefore, recording of level-down information, which is information for dropping the laser level to the reproduction level immediately before the servo pattern, and recording of level-up information, which is information for returning the laser level to the recording level immediately after the servo pattern. Records are required. However, the level-down information and the level-up information are control information necessary only at the time of recording, and are information not necessary in the ROM area which is a read-only area. Therefore, as shown in FIG. 26, this optical disc is provided with a POST area in which the level-down information is recorded and a PRE area in which the level-up information is recorded only in the RAM area. As a result, the POST area and the PRE area, which are supposed to be provided in the ROM area and should be recorded, can be omitted. Therefore, since the POST area and the PRE area can be omitted, the storage capacity of the ROM area can be improved, and thus the storage capacity of the entire optical disk can be improved.

Next, in the above optical disc, the above R
The track pitch of the OM area is made narrower than the track pitch of the RAM area. In the ROM area, the data level obtained at the time of reproduction is higher than the data level obtained from the RAM area, and thus the recorded data can be reproduced without any problem even in this case. Therefore, the ROM
As the track pitch of the area is narrowed, the storage capacity of the ROM area can be improved, and thus the storage capacity of the entire optical disk can be improved.

Next, in the ROM area, since the data level obtained during reproduction is higher than the data level obtained from the RAM area, the data level obtained during reproduction is RA.
Since it is higher than the data level obtained from the M region,
Even if the linear density of the OM area is smaller than that of the RAM area, the recorded data can be reproduced without any problem. Therefore, in the optical disc, the linear density of the RAM area is 0.41 μm as shown in FIG. 27A, while the linear density of the ROM area is 0 as shown in FIG. The linear density of the ROM area is higher than that of the RAM area. As a result, the storage capacity of the ROM area can be improved by the increase in the linear density, and the storage capacity of the entire optical disk can be improved. In this case, the storage capacity of the RAM area is 627.148 MB as shown in FIG. 26A, while the storage capacity of the ROM area is 63 as shown in FIG.
It could be 9.843 MB.

Next, if there is a defect such as a scratch on the optical disk, the recording data cannot be recorded at the defective position. Therefore, a replacement information recording area (DMA area: Defe) for recording the replacement information indicating the defective position.
(ct Management Area) is provided, and it is necessary to record the record data while avoiding the defect position by reproducing this alternation information at the time of recording. However, this replacement information is almost unnecessary in the ROM area formed by pressing.
Therefore, the optical disc has a DMA area provided only in the RAM area of the ROM area and the RAM area.

Specifically, the optical disc shown in FIG.
As shown in (a), the ROM area and the RAM area are respectively a first ROM area, a first RAM area, and a second RO area.
The M area and the second RAM area are provided in this order, and the DMA area is the first area as indicated by the hatched area in FIG.
Of the RAM area and the tail of the second RAM area.

As a result, D which should be provided in the ROM area
Since the MA area can be omitted, the storage capacity of the entire optical disc can be improved.

In the optical disc, the RAM area and the ROM area are divided into first to third areas as shown in FIG. 28 (b).
The RAM area may be continuously provided, and then the ROM area may be provided. In this case, the DMA area is
As shown by the diagonal lines in FIG. 28B, they are provided at the beginning of the first RAM area and the tail of the third RAM area, respectively.
Even in this case, since the DMA area which should be provided in the ROM area can be omitted, the storage capacity of the optical disk can be improved.

Next, when forming an optical disk, a pinhole P of, for example, about 80 μm to 100 μm may occur as shown in FIG. This pinhole P is the RA
If it occurs in the M area, since the DMA area is provided in the RAM area as described above, this is stored by storing the position where the pinhole P is generated as the replacement information. Recording data can be recorded / reproduced so as to be avoided. However, in the case of the ROM area, since the recording data is previously formed by embossed pits or the like, the recording data can be recorded avoiding the pinhole P. Can not. Therefore, if the pinhole P is generated, the optical disc itself becomes a defective product.

Here, when the recording data is recorded on the optical disk, the error correction information (parity data) is recorded, and the correction capability by this parity data is one sector. For this reason, if the pinhole P occurs between two tracks, error correction becomes impossible.
Even if the parity data is added, if it is added to each sector, the storage capacity will be reduced by the parity data.

Therefore, in the ROM area of the optical disk, the track pitch is set so as to be completed for each recording track circumference as shown in FIG. 29, and has a track pitch larger than the diameter of the pinhole P, for example, 1. Data sectors D are formed with a track pitch of 21 μm. Also, FIG.
(A) As indicated by the shaded area, parity data for performing error correction on the recorded data is collectively recorded at the end of each zone from zone 0 to zone 15.

Specifically, taking the zone 0 as an example,
This zone 0 is, as shown in FIG. 31, sector 0 to sector 9, sector 10 to sector 19, sector 20 to sector 29.
One block consists of 10 sectors like ...
One group is formed by collecting 60 blocks, and this group is formed by collecting 130 groups. There are 2080 blocks in one zone, and the total is 2
It has 0800 sectors. Note that each of the zones 0 to 14 has 20800 sectors, but only the last zone, zone 15, has 9100 sectors. Each of the above zones 0 to 14 208
Of the 00 sectors, the substantial recording data excluding the servo patterns and the like is 18900 sectors, and among the 9100 sectors of the zone 15, the substantial recording data excluding the servo patterns and the like is 8190 sectors. It is a sector. When parity data is added to each zone, one parity sector is formed for 10 data sectors.

That is, one sector has 2352 bytes, of which the actual recording data excluding the servo pattern and the like is 2088 bytes. Therefore, the parity sector is formed by taking the exclusive OR of the recording data of 2088 bytes. As a result, in the case of the zones 0 to 14, a parity sector for one sector is added after the 18900 sectors as shown in FIG. 32, and in the case of the zone 15, as shown in FIG. A parity sector for one sector is added after the sector.

As a result, the pinhole generated when the medium is formed does not shunt into two tracks, and it is possible to correct the error using the parity data. In addition, since the parity data is collectively recorded, the number of parity data to be added can be reduced and the storage capacity can be improved. The number of parity sectors in this case is 29247, which is 58.35 MB (1890 × 15 + 82), as compared with the case where a parity sector is added to each data sector.
7) The storage capacity of minute recording data can be increased.

The parity sector is the ROM
You may make it record at the end of an area collectively. In this case, zone 0 to zone 14 are set to 1 as shown in FIG.
13 sets of 10 sectors are extracted at intervals of 600 sectors, one parity sector is formed for the 130 data sectors, and the data is collectively recorded at the end of the ROM area.
As shown in the figure, every 500 sectors has 10 sectors and 13
A group is extracted, one parity sector is formed for this 130 data sectors, and the data is collectively recorded at the end of the ROM area. As a result, the number of parity sectors can be set to 2450, and the capacity reduction for the parity sectors can be suppressed to 4.9 MB (2450 × 2K). Therefore, the storage capacity of the optical disk can be improved as compared with the case where the parity sector is added to each zone.

Next, the second disc-shaped recording medium according to the present invention will be described.
The embodiment will be described. In the above description of the first embodiment, the ROM area can omit the reference area for recording the reference pattern because the writing position can be accurately specified by the press accuracy. By recording the pattern in advance, it is possible to reproduce the recorded data in the ROM area more accurately. However, if a reference pattern is recorded at the beginning of all the sectors, the storage capacity will be reduced.

Therefore, in the second embodiment, the reference area is provided at the beginning of each zone of the optical disk, and the reference pattern is recorded in the reference area.

As a result, the recorded data in the ROM area can be reproduced more accurately by the reference pattern, and the number of reference areas provided in the ROM area can be suppressed to 16 so that each sector can be reproduced. It is possible to improve the storage capacity more than when the reference pattern is recorded.

In this case, the reference area provided in the ROM area may be provided only at the head of the ROM area. As a result, the storage capacity can be further improved as compared with the case where the reference area is provided for each head of each zone.

Next, the third embodiment of the disk-shaped recording medium according to the present invention.
The embodiment will be described. In the above description of the first and second embodiments, the disc-shaped recording medium according to the present invention is applied to an optical disc having a RAM area and a ROM area, which is as shown in FIG. 9 (b). It can be applied to an optical disc in which the user area is entirely a ROM area (Embossed Zone).

Like the optical disc according to the first embodiment, the optical disc according to the third embodiment has a track pitch of, for example, 1.21 μm so that the track pitch is equal to or larger than the diameter of the pinhole P. A data sector D is formed with high linear density and track completion, and a parity sector is collectively recorded for each zone.
Further, similarly to the optical disc according to the second embodiment, a reference area is provided at the beginning of each zone,
The reference pattern is recorded here. As a result, the storage capacity can be improved similarly to the optical discs according to the first and second embodiments described above.

In this case as well, the parity sector may be recorded at the end of the disc, and the reference area may be provided at the end of the disc and the reference pattern may be recorded there. As a result, the storage capacity can be further improved.

Next, the recording / reproducing apparatus for recording / reproducing the record data to / from the optical disc of such a format is an optical disc having the RAM area and the ROM area, which are the optical discs according to the first and second embodiments. Recording and reproduction of a magnetic disk and reproduction of a magneto-optical disk having only a ROM area, which is the optical disk according to the above-mentioned third embodiment, are possible. For example, as shown in FIG. Drive 200 and S
Commands and data are exchanged with the host computer 300 connected via the CSI interface.

The process for passing the command and data is performed by the controller 10 of the control circuit block 100.
It is performed by 1. At the time of recording, the controller 101 performs C operation on the data from the host computer 300.
RC, error correction code, etc. are added and passed to the disc drive 200, and at the time of reproduction, the disc drive 20
The error correction is performed on the data from 0 and only the user data portion is transferred to the host computer 300. Further, a command for the servo system and each block of the disk drive 200 performs a necessary processing for the command from the controller 101, and a digital signal processing circuit (DSP).
Performed by 102.

In this recording / reproducing apparatus, the DSP 102
The magneto-optical disk 201 is loaded in response to a request from the host computer 300 with the magneto-optical disk 201 mounted on the spindle motor 203 by the loading mechanism 202, or when the automatic spin-up mode is set. And I / O block 1
A command is issued to the spindle driver 204 via 03 to rotate the spindle motor 203. And
The spindle driver 204 is the spindle motor 203.
Outputs a lock signal when the number of rotations reaches a predetermined value, and DSP1
Notify 02 that rotation is stable. Further, during this period, the DSP 102 moves the pickup 205 to the outer or inner circumference side by the pickup driver 105 via the pulse width modulation (PWM) circuit 104 so that the beam spot is located outside the user area.

When the focus is pulled in the user area, the data on the disc having high sensitivity may be erased by mistake. However, by pulling the focus in the above-mentioned GCP zone or the like outside the user area, Such erroneous erasure can be prevented.

When the spindle motor 203 rotates at a constant speed and the pickup 205 moves to the outer peripheral side, for example, DS
P102 is the I / O block 106 to the D / A converter 1
The bias current LDbias of the laser diode 207 provided in the pickup 205 is set to the laser driver 206 via 07.
A command is issued to the servo system timing generator (STG) 108 for controlling the ON / OFF of the laser so that the laser is emitted. When laser light is emitted from the laser diode 207, laser light enters the photodetector 208 provided in the pickup 205, and the detection output by the photodetector 208 is current / voltage (IV).
It is input to the multiplexer 109 via the conversion & matrix amplifier 209 as a front APC signal converted into a voltage by the IV conversion block.

This front APC signal is A / A as a signal selected by the multiplexer 109 in a time division manner.
It is digitized by the D converter 110 and input to the DSP 102 via the I / O block 111. DSP10
2 recognizes the light quantity of the laser light from the digitized front APC signal, and outputs the light quantity control data calculated by a digital filter to the I / O block 106.
From the laser driver 206 via the D / A converter 107
By returning to the laser diode 207.
The laser power of is controlled so as to be constant.

Next, the DSP 102 has the PWM circuit 104.
By passing a current from the above to the focus driver of the pickup driver 105, the focus actuator of the pickup 205 is driven up and down to enter the focus search state. At this time, the laser light reflected from the magneto-optical disk 201 is detected by the photodetector 208, and the detection output by this photodetector 208 is I-.
The multiplexer 109 converts the voltage into a voltage by the IV conversion block of the V conversion & matrix amplifier 209 and outputs it as a focus error signal via the matrix amplifier.
Is input to

This focus error signal is digitized by the A / D converter 110 as a signal time-divisionally selected by the multiplexer 109 similarly to the front APC signal, and is digitized by the DSP 1 via the I / O block 111.
It is input to 02. The DSP 102 applies the focus control data obtained by digitally filtering the digitized focus error signal to the P
By feeding back from the WM circuit 104 to the focus driver of the pickup driver 105, a servo loop for focus control is formed. When the focus control becomes stable, the RF signal obtained from the detection output of the photodetector 208 by the IV conversion & matrix amplifier 209 has a certain amplitude, and after being clamped to an appropriate potential by the selector & clamp 112, A A / D conversion is performed by the / D converter 113.

The clock at this time becomes the frequency of the free running state of the servo system clock generation (SPLL) circuit 114. A signal obtained by dividing the frequency of the free run by a predetermined value is also used as the clamping timing pulse.

The SPLL circuit 114 includes the A / D converter 11
The pit pattern is checked by looking at the amplitude difference of the RF signal digitized by 3, and the same pattern as the pit row in the servo area is searched. Then, when a pattern is found, the clock selector 115 is controlled so as to open a window at the position where the next pattern should appear, and it is confirmed again whether the patterns match. When this operation is continuously confirmed a certain number of times, it is considered that the SPLL circuit 114 has locked the disk. The phase information is obtained by taking the amplitude difference between both shoulders of the wobble pit in the servo area. Further, by adding the phase information obtained from both of the two wobble pits, the fluctuation of the gain caused by the amplitude change due to the tracking position is absorbed.

When the SPLL circuit 114 is locked, the position of each segment becomes clear, and the position of the segment mark pit can be recognized. As shown in FIG.
The clock selector 115 is controlled so as to open a window at four positions A, B, C and D, and the four positions A, B, and
A position having the maximum amplitude is searched for in the RF signals sampled by C and D. When the result is A, it is an address mark, this segment is an address segment, and the beginning of the frame can be recognized.
Frame synchronization can be achieved by clearing the frame counter. Since one frame is composed of 14 segments, the clock selector 115 is controlled so that a window is opened every 14 segments, and when it can be continuously recognized as an address mark, it is determined that the frame synchronization is locked.

Since the position where the address is recorded can be recognized when the frame synchronization is applied, the address decoder (A
The DEC) 116 decodes the track address and the frame code. This ADEC 116 is performed by observing a pattern in which each 4 bits are gray-coded, matches the gray code table shown in FIG. Here, in the ADEC 116, the reproduced signals at the respective positions a, b, c, d shown in FIG. 4 are sampled, and the position where the amplitude value is maximum is found by the maximum difference detection method (differential detection method).
Similarly, the reproduced signals at the respective positions e, f, g, and h shown in FIG. 4 are sampled, the position where the amplitude value thereof is maximized is obtained, and decoding is performed by the combination thereof and the gray code table. Track address [A
M] to [AL], parity [P], frame addresses [FM] and [FL] are decoded, and the result is stored in a register. The DSP 102 reads out this register when these data are confirmed, and the pickup 2
The current position of 05 can be detected. However, since it is greycoded not only for 4 bits but for the whole, it is not a simple match, but the LSB of the upper 4 bits.
Is compared with the inverted table depending on whether is "1" or "0". Here, load the first decoded frame code into the frame counter, compare the numerical value obtained by incrementing this frame counter for each frame with the actual reproduced frame code, and continuously match them. When confirming, it is assumed that the rotation is synchronized. After that, the numerical value obtained by the frame counter is returned to the DSP 102 as a frame code so that the frame position is not erroneously recognized even if there are some defects.

The address decoder (ADEC) 11
6 decodes the GCP information in the same manner as the track address and frame code. However, not the address segment but the GC in which the GCP information is recorded
The contents of the GCP area ARgcp can be confirmed by reading the register contents in the P segment GCPseg.

The DSP 102 also picks up the pickup 2 while reading the gray-coded track address.
By calculating the speed of 05 and controlling the slide motor of the pickup 205 from the PWM circuit 104 via the slide driver of the pickup driver 105,
The pickup 205 is moved to the target truck.

Then, when the pickup 205 arrives at the target track, the tracking operation is started. As described above, the tracking error signal is obtained by taking the difference between the amplitude values of the RF signal for the two wobble pits in the servo area. The DSP 102 forms a servo loop for tracking control by feeding back tracking control data obtained by digitally filtering this value from the PWM circuit 104 to the galvano driver and the slide driver of the pickup driver 105. The slide driver drives the slide motor to control the fluctuation of the low frequency component, and the galvano driver drives the galvano motor of the pickup 205 to perform tracking control so that the laser spot is located at the center of the track. To do.

The head position of the target sector is detected with tracking applied. As described above, there is a sector mark in the segment at the beginning of each sector and the segment immediately before it, and each sector mark has the sector mark 4 shown in FIG.
The clock selector 115 is controlled so as to open a window at four positions A, B, C and D, and the four positions A, B, and
When the position where the maximum amplitude is among the RF signals sampled by C and D is B, it indicates that it is the head segment of the sector, and when it is C, it is the segment immediately before the head of the sector. Indicates. Basically, the segment at the beginning of the sector is determined by converting the sector address given by the host computer 300 into a physical sector and calculating which segment of which track the sector is. The probability that the two types of sector marks become defective at the same time is empirically 10-10 or less, and the probability of defective sectors due to this is extremely small.

Further, the data clock generation (DPLL) circuit 117 outputs the servo clock sclk obtained by the SPLL circuit 114 and synchronized with the frame M / N.
A doubled data clock dclk is generated, and this data clock dclk is generated by the data system timing generator 1.
19 and the recording / reproducing circuit 120.

The recording / reproducing circuit 120 is supplied with recording data from the host computer 300 via the controller 101 in the recording operation mode. Then, the recording / reproducing circuit 120 performs a scrambling process according to Y = X7 + X on a sector unit basis by adding (EXOR) a random number of 127 cycles to the recording data, and the scrambled recording data is recorded as described above. The data is modulated into NRZI series data synchronized with the data clock dclk. At this time, the initial value is set to “0” for each segment. Then, the modulated signal wdat is supplied to the magnetic head 211 via the magnetic head driver 210. The magnetic head 211 generates a magnetic field according to the modulation signal wdat, and applies this magnetic field to the data area ARd of the magneto-optical disk 201 which is overheated to the Curie temperature by the laser beam emitted by the laser diode 207. , NRZI series data is recorded.

In the reproduction operation mode, the reproduction MO signal obtained by the IV conversion & matrix amplifier 209 from the detection output of the photodetector 208 is
After being clamped to an appropriate potential by the selector & clamp 112, it is A / D converted by the A / D converter 113 and supplied to the recording / reproducing circuit 120. Then, the recording / reproducing circuit 210 performs digital filter processing on the reproduced MO signal digitized by the A / D converter 113 so as to match the partial response (1, 1), and then produces NRZI series data by Viterbi decoding. Reproduce. Then, the NRZI series data is converted into NRZ system in segment units, then descrambled in sector units and then converted into reproduction data, and the reproduction data is transferred to the host computer 300 via the controller 101.

By scrambling the recorded data in this way, the data pattern is randomized, the probability that undetermined paths will continue during Viterbi decoding is reduced, and the memory capacity can be reduced. By randomizing the pit arrangement on the ROM disk, the ratio of the presence or absence of pits on the board surface approaches 50%, and disk molding can be facilitated.

As described above, the magneto-optical disk 201 is used.
Since the (optical disk) can have a large capacity, the magneto-optical disk 201 can be downsized. Therefore, the miniaturization of the turntable and the like of the magneto-optical disc 201 can contribute to the miniaturization of the recording / reproducing apparatus.

The disc-shaped recording medium according to the present invention can be applied to other disc-shaped recording media such as so-called compact discs, write-once and magnetic discs in addition to the magneto-optical disc 201. Of course, various modifications can be made without departing from the technical idea of the present invention.

[0103]

The disk-shaped recording medium according to the present invention can improve the overall storage capacity. Therefore, the disc-shaped recording medium itself can be miniaturized, and recording or reproduction for a long time can be performed, and a compact recording / reproducing device or the like for performing recording or reproduction on the disc-shaped recording medium. And cost reduction.

[Brief description of drawings]

FIG. 1 is a diagram showing a segment structure of a disc-shaped recording medium according to the present invention.

FIG. 2 is a diagram showing a format of a servo area on the optical disc.

FIG. 3 is a diagram showing a method of detecting a first pit in a servo area on the optical disc.

FIG. 4 is a diagram showing a format of an access code recorded in an address segment on the optical disc.

FIG. 5 is a diagram showing a part of the access code.

FIG. 6 is a diagram showing a format of a data segment on the optical disc.

FIG. 7 is a diagram showing a format of a servo area in a ROM disc.

FIG. 8 is a diagram showing a reference pattern of a data sector on the optical disc.

FIG. 9 is a diagram showing a setting state of zone division in the optical disc.

FIG. 10 is a diagram showing a state of zone division in the optical disc.

FIG. 11 is a diagram showing a data sector format in the optical disc.

FIG. 12 is a diagram showing an arrangement state of GCP segments on the optical disc.

FIG. 13 is a diagram showing a structure of the GCP segment.

FIG. 14 is a diagram showing a relationship between a page number of a GCP segment and a frame address of an address segment on the optical disc.

FIG. 15: GC of page number 1 of the GCP segment
It is a figure which shows the content of P information.

FIG. 16: GC of page number 2 of the GCP segment
It is a figure which shows the content of P information.

FIG. 17: GC of page number 3 of the above GCP segment
It is a figure which shows the content of P information.

FIG. 18: GC of page number 4 of the GCP segment
It is a figure which shows the content of P information.

FIG. 19: GC of page number 5 of the above GCP segment
It is a figure which shows the content of P information.

FIG. 20: GC of page number 6 of the GCP segment
It is a figure which shows the content of P information.

FIG. 21: GC of page number 7 of the GCP segment
It is a figure which shows the content of P information.

FIG. 22: GC of page number 8 of the GCP segment
It is a figure which shows the content of P information.

FIG. 23: GC of page number 9 of the GCP segment
It is a figure which shows the content of P information.

FIG. 24 G of page number 10 of the GCP segment
It is a figure which shows the content of CP information.

FIG. 25 is a diagram for explaining a reference area provided on the optical disc.

FIG. 26 is a diagram for explaining a POST area and a PRE area provided before and after the servo pattern of the optical disc.

FIG. 27 is a diagram for explaining the linear density of the optical disc.

FIG. 28 is a diagram for explaining the position of a DMA area provided on the optical disc.

FIG. 29 is a diagram for explaining a track pitch of data sectors formed on the optical disc.

FIG. 30 is a diagram for explaining the position of a parity sector provided on the optical disc.

FIG. 31 is a diagram for explaining the recorded contents of zone 0 of the optical disc divided into the 16 zones.

FIG. 32 is a diagram for explaining a parity sector added to each zone of the optical disc.

[Fig. 33] Fig. 33 is a diagram for explaining parity sectors collectively recorded at the disc end of the optical disc.

FIG. 34 is a block diagram of a recording / reproducing apparatus for recording / reproducing the optical disc.

[Explanation of symbols]

 ASEG Address segment DSEG Data segment ARs Servo area ARd Data area ARpr Prewrite area ARpo Postwrite area Pa, Pb, Pc Servo pit 100 Control block 101 Controller 102 DSP 103, 106, 111 I / O block 104 PWM circuit 105 Pickup driver 107 D / A converter 108 Servo system timing generator 109 Multiplexer 110,113 A / D converter 112 Selector & clamp circuit 114 Servo system clock generation circuit 115 Clock selector 116 Address decoder 117 Data system clock generation circuit 119 Data system timing generator 120 Recording / Playback circuit 200 Disk driver 201 Magneto-optical disk 20 5 Pickup 206 Laser Driver 207 Laser Diode 208 Photo Detector 209 IV & Matrix Amplifier 210 Magnetic Head Driver 211 Magnetic Head 300 Host Computer

Claims (8)

[Claims] 1. A disk-shaped recording medium having a reproduction-only area and a recording / reproducing area, wherein a reference pattern used as a reference when reproducing recorded data is recorded only in the recording / reproducing area. Recording medium. 2. A disc-shaped recording medium having a read-only area and a recording / playback area, wherein the read-only area has a narrower track pitch than the record-playback area. 3. A disk-shaped recording medium having a read-only area and a recording / playback area, wherein the read-only area has a higher linear density than the record-playback area. 4. A disc-shaped recording medium having a reproduction-only area and a recording / reproducing area, wherein alternation information indicating a defective position is recorded only in the recording / reproducing area. . 5. A disk servo recording medium of a sample servo system having a read-only area and a recording / reproducing area, and servo areas in which servo patterns are recorded at predetermined intervals, wherein each servo of the recording / reproducing area is provided. The level-down information recording area is provided in the preceding stage of the area and in which the level-down information for setting the laser level of the recording level as the reproduction level is recorded. A disc-shaped recording medium, comprising: a level-up information recording area in which level-up information for re-recording a laser level set as a recording level by information is recorded. 6. A reference that has at least a reproduction-only area and is used as a reference when reproducing recorded data, at the beginning of the reproduction-only area or at the beginning of each area obtained by dividing the reproduction-only area into a plurality of areas. A disk-shaped recording medium characterized in that a pattern is recorded. 7. The disc-shaped recording medium according to claim 6, further comprising a recording / reproducing area together with the reproduction-only area. 8. A read-only area is provided at least, and a data sector is formed in the read-only area at a track pitch equal to or larger than the diameter of a pinhole generated on a medium and completed at each track circumference. Error correction information for performing error correction of recorded data is collectively recorded at the end of the reproduction-only area or at the end of each area obtained by dividing the reproduction-only area into a plurality of areas. A disk-shaped recording medium characterized by the following.